From José's most recent presser remarks, if anything he gave this rumour more oxygen to burn.
Kind of 50/50 on Matic (more 25/75 in all honesty), here's why.
On one side, JM being the manager knows what players he needs to fulfill certain positional needs and he obviously rates Matic + has a proven history with him. Matic would be a flavourless signing in that he'll get the job done, you'd know what you're getting in him, and the level he's at atm is pretty much as good as it'll get with him (already showing initial signs of slowing down/decline) ....on the other hand, there's a youngster in Fabinho who'll be worth slightly more but will be someone who can grow with the new core and give us many years of prime production while being a tasteful addition to the squad.
However, there's also a fine line between having proven players in which you know for certain what they'll be able to bring to the table vs having younger players who are raw but promising and just need playing time to cement themselves as viable options. Pretty much carbon copies of what's happened with Lukaku/Rashford and hopefully soon to be Perisic/Martial; there's a proven guy and an up and coming guy who both offer different dynamics while also creating healthy competition amongst one another. Using the same logic for the CDM situation, I prefer Fabinho 75-25 over Matic strictly because we already have the proven guy in Carrick. Matic is up there in age himself and like I said is already showing signs of slowing down. Yes he's the same age as Perisic but Perisic has a handful of prime years left in him whereas Matic has added up a ton of mileage over the years and clearly has more wear and tear on his body / will lead to him declining sooner than Perisic. I just think it'd be more cost effective for United to buy Fabinho, instead of buying Matic at a similar cost + having to spend even more money down the road to buy his replacement in a couple years time. But what's money to United anyways? Fact of the matter is they'll buy anyone who they deem best suited for the team regardless of what stage they are at in their career.
And then there's the aspect of JM wanting his style of player aka the specialist. Just as he did with Lukaku, he wanted a target man and got his guy over other market options. Similarly here, I'm certain he wants a destroyer in which case you can't blame him for pursuing Matic. Fabinho is more well rounded compared to Matic in that he can dribble, has vision, and can make the regular long pass. He's physically gifted too being his greatest attribute but he's just quite not at that destroyer level which Matic is. A point can be made how Lukaku/Rashford and Perisic/Martial will/would offer different dynamics at their positions, likewise so would Matic/Carrick. Carrick is a lot closer to the type of player Fabinho is vs Matic in that he's sound with the ball and has the ability to hit open guys (ball skills). So it makes sense in that regard if Mourinho chose Matic because there'd be a bigger discrepancy in Matic/Carrick vs Carrick/Fabinho; a broader spectrum to pick and choose a lineup from against specific opponents.
...take that all into consideration and you have to respect whichever one it ends up being. Matic essentially means José is going for the conservative approach and wants to be as competitive as possible now (which again you can't blame with his and the clubs ambitions + Mourinho's amazing trackrecord during the 2nd year at clubs). Fabinho means José would be more flexible into slowly incorporating him into the squad, waiting a year or 2's time, while moulding him into the destroyer sepcialist he seeks but also lessening the chances of being as good of a team as possible right now. Which also means lowering odds of competing for the league having more so of an experiment than a sure thing in Fabinho but again, an argument could be made we can afford to take on the younger player in Fabinho over Matic since we already have that sure thing in Carrick who would make any potential growing pains very reasonable to cope with.
Because of the latter, I'd personally prefer Fabinho 75-25. One time buy (also the sexier buy) who'd grow with the core instead of Matic, then buying his replacement shortly after which would only disrupt chemistry and the flow of the club.
BUT I won't be engulfed in rage if we get Matic over him either
If José thinks it's that big of a difference between the 2 that he has to get Matic to maintain a certain level of squad certainty, then so be it - it'd only mean he's that more inclined to win now than later so no way you can be upset at that. Wouldn't be the end of the world by any means and José pretty much has to be dead certain Matic works to a tee to justify the risk-reward in choosing one over the other otherwise there'll be a considerable amount of backlash as with anything as
controversial such as this.
Long ass fecking read, my apologies but def worthwhile. Just shedding light on the CDM situation and showing both sides of the story. Please don't get mad at me 
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